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Updated: May 28, 2026

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Photoisomerization in different classes of azobenzene
H M Dhammika Bandara1, Shawn C Burdette
1University of Connecticut, 55 North Eagleville Road, Storrs, CT 06269-3060, USA.
Abstract:
Azobenzene undergoes trans→cis isomerization when irradiated with light tuned to an appropriate wavelength. The reverse cis→trans isomerization can be driven by light or occurs thermally in the dark. Azobenzene's photochromatic properties make it an ideal component of numerous molecular devices and functional materials. Despite the abundance of application-driven research, azobenzene photochemistry and the isomerization mechanism remain topics of investigation. Additional substituents on the azobenzene ring system change the spectroscopic properties and isomerization mechanism. This critical review details the studies completed to date on the 3 main classes of azobenzene derivatives. Understanding the differences in photochemistry, which originate from substitution, is imperative in exploiting azobenzene in the desired applications.
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